1. Field of the Invention
The present invention relates to the field of computer systems. More specifically, embodiments of the present invention relate to a method and apparatus for supplying power to a portable computer system and to a peripheral device.
2. Related Art
As the components required to build a computer system have reduced in size, new categories of computer systems have emerged. One of the new categories of portable computer systems is the xe2x80x9cpalmtopxe2x80x9d computer system. A palmtop portable computer system is a computer that is small enough to be held in the hand of a user and can be xe2x80x9cpalm-sized.xe2x80x9d Most palmtop computer systems are used to implement various Personal Information Management (PIM) applications such as an address book, a daily organizer and electronic notepads, to name a few.
Because of the limited size of palmtop portable computer systems, battery power is typically limited to one or two AAA or smaller batteries. This limits the operations that can be performed by the palmtop portable computer system.
The latest generations of palmtop portable computer systems are enhanced with the capability of coupling to a variety of peripheral devices. This gives their user access to a large amount of additional features. However, peripheral devices often use quite a lot of power. Therefore, many peripheral devices often include their own power source such as, for example, rechargeable batteries.
The use of a portable computer system and a peripheral device that is connected to the portable computer system can be limited by either the batteries in the peripheral device running out of charge or the batteries in the portable computer system running out of charge. In many instances the batteries in the peripheral device run out before the batteries in the portable computer system. The user must then discontinue usage of the peripheral device, even when there is significant charge left in the batteries of the portable computer system. Also, the batteries in the portable computer system can run out before the batteries in the peripheral device. The user must then discontinue usage of the portable computer system, even when there is significant charge left in the batteries of the peripheral device.
What is needed is a method and apparatus for controlling operating time of a portable computer system and a peripheral device. Also, a method and apparatus is needed that maximizes operating time of the portable computer system and the peripheral device.
The method and apparatus of the present invention allows for controlling operating time of a portable computer system and a peripheral device. Also, the method and apparatus of the present invention allows for maximization of operating time of the portable computer system and the peripheral device.
A portable computing system is disclosed that includes a rechargeable power supply. The portable computing system also includes a connection mechanism for coupling to a peripheral device having a rechargeable power supply. The portable computing system also includes a charging control module coupled to the rechargeable power supply and coupled to the connection mechanism that includes logic for determining the operating time for the portable computer system and for the peripheral device. The charging control module is operable for charging either the rechargeable power supply of the peripheral device or the rechargeable power supply of said portable computer system so as to control the operating time for the portable computer system and the peripheral device.
A peripheral device is disclosed that includes a rechargeable power supply. The portable computing system also includes a connection mechanism for coupling to the connection mechanism of the portable computer system. A boost circuit that is coupled to the rechargeable power supply and that is coupled to the connection mechanism, increases the voltage from the rechargeable power supply of the peripheral device to a voltage sufficient to charge the rechargeable power supply of the portable computer system. A boost charging circuit that is also coupled to the rechargeable power supply and coupled to the connection mechanism increases voltage received from the portable computer system to a voltage sufficient to charge the rechargeable power supply of the peripheral device. In the present embodiment the peripheral device also includes a controller that is operable upon receiving instructions from the portable computer system to cause the boost circuit to send power to the portable computer system.
A method for controlling the operating time of a portable computer system and a peripheral device that is coupled to the portable computer system is disclosed. Charge within the rechargeable power supply of the portable computer system and charge within the rechargeable power supply of the peripheral device is determined. The determined charge for the portable computing system and for the peripheral device is then used to determine operating time for the portable computing device and operating time for the peripheral device. Operating time is an indication of the amount of time that the device will continue to operate given its remaining battery charge.
In one embodiment, a pop-up menu is displayed on the display screen of the personal computing system that allows the user to select a desired option (e.g., maximizing operating time of the portable computer, maximizing operating time of the peripheral device, or maximizing the life of the entire system). In the present embodiment, this pop-up menu is displayed when power is determined to be low in either the portable computing system or in the peripheral device.
When operating time of the portable computer system is to be maximized, power is sent from the peripheral device to the portable computer system to extend the operating time of the portable computer system. Similarly, when operating time of the peripheral device is to be maximized, power is sent from the rechargeable power supply of the portable computer system to the peripheral device to extend the operating time of the peripheral device.
When operating time of the entire system is to be maximized, power is moved such that the operating time for the portable computer system is equal to the operating time of the peripheral device. Thereby the operating time for the portable computing system and the peripheral device together are maximized.
Accordingly, the method and apparatus of the present invention allows for controlling operating time of a portable computer system and a peripheral device. Also, the method and apparatus of the present invention allows for maximization of operating time of the portable computer system and the peripheral device. Moreover, a user can maximize operating time of one component, either the operating time of the portable computer system or the peripheral device.